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Config on the remote site
Create a contact group on the remote site.
Setup → Users → Contact Groups → Add Group
.Assign hosts and services to this contact group.
For Hosts
Setup → Hosts → Host monitoring Rules → Assignment of hosts to contact groups → Add rule
For Services
Setup → Services → Service monitoring rules → Assignment of services to contact groups → Add rule
.Assign the contact group to the user.
Setup → Users → Edit User.
Config on the central site
Setup → Users → Edit User
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